ought1 / ôt/ • modal verb (3rd sing. present and past ought) 1. used to indicate duty or correctness, typically when criticizing someone's actions: they ought to respect the law it ought not to be allowed. ∎ used to indicate a desirable or expected state: he ought to be able to take the initiative. ∎ used to give or ask advice: you ought to go.2. used to indicate something that is probable: five minutes ought to be enough time.ought2 • n. archaic term for aught2 .ought3 • pron. variant spelling of aught1 .